my solution for problem 1380

note: the script for creating a new note for the daily problem seems to be stuck in the queue, so i've created this one manually.  i'll delete the "jeremymanning.md" note if that action ever runs!

Author: jeremymanning

problems/1380/jeremy.md

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+# [Problem 1380: Lucky Numbers in a Matrix](https://leetcode.com/problems/lucky-numbers-in-a-matrix/description/)
+
+## Initial thoughts (stream-of-consciousness)
+- Let's use set comprehensions to compute the minimum values in each row (`row_mins`) and the maximum values in each column (`column_maxes`)
+- Then we can just return `list(row_mins.intersect(column_maxes))`
+
+## Refining the problem, round 2 thoughts
+- Since every element in the matrix is distinct (per the problem definition), we don't need to deal with the same value potentially appearing in different rows/columns (otherwise we'd also need to track the positions)
+
+## Attempted solution(s)
+```python
+class Solution:
+    def luckyNumbers (self, matrix: List[List[int]]) -> List[int]:
+        # compute the minimum for each row
+        row_mins = {min(r) for r in matrix}
+
+        # compute the maximum for each column
+        n = len(matrix[0])
+        column_maxes = {max([r[i] for r in matrix]) for i in range(n)}
+
+        # return a list of the set intersection between the mins and maxes
+        return list(row_mins.intersection(column_maxes))
+```
+- Given test cases pass
+- I don't think there are other special cases we need to account for that this solution won't cover; submitting...
+
+![Screenshot 2024-07-18 at 8 26 55 PM](https://github.com/user-attachments/assets/e855d252-0c1d-4d8c-afba-fdcbde8e319f)
+
+Solved!